U.S. patent application number 14/333989 was filed with the patent office on 2015-02-05 for tank pressure control solenoid with passive tank vacuum relief.
The applicant listed for this patent is Continental Automotive Systems, Inc.. Invention is credited to David W Balsdon, Brian Woods.
Application Number | 20150034180 14/333989 |
Document ID | / |
Family ID | 52426557 |
Filed Date | 2015-02-05 |
United States Patent
Application |
20150034180 |
Kind Code |
A1 |
Balsdon; David W ; et
al. |
February 5, 2015 |
TANK PRESSURE CONTROL SOLENOID WITH PASSIVE TANK VACUUM RELIEF
Abstract
A tank pressure control valve which provides for both controlled
and passive vacuum relief functions with an additional component in
a tank purge valve. The tank pressure control valve includes a
second valve in addition to a purge valve to create a small sealing
area on one side that opens easily against the tank pressure with
the normal magnetic forces in a purge valve. The second valve is a
sealing disk, which has an aperture to allow for the flow of purge
vapor. One side of the disk has sealing on a larger area so the
small vacuum forces open the valve against the spring force biasing
the valve to a closed position. The design of the second valve uses
a disk to provide precise flow control and passive vacuum
relief.
Inventors: |
Balsdon; David W; (Chatham,
CA) ; Woods; Brian; (Chatham, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Continental Automotive Systems, Inc. |
Auburn Hills |
MI |
US |
|
|
Family ID: |
52426557 |
Appl. No.: |
14/333989 |
Filed: |
July 17, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61861576 |
Aug 2, 2013 |
|
|
|
Current U.S.
Class: |
137/493 |
Current CPC
Class: |
F02M 25/0836 20130101;
F16K 31/0655 20130101; Y10T 137/7771 20150401; F16K 24/06
20130101 |
Class at
Publication: |
137/493 |
International
Class: |
F16K 24/00 20060101
F16K024/00 |
Claims
1. An apparatus, comprising: an valve assembly, including: a
housing; an actuator disposed within the housing; a cavity formed
as part of the housing, the cavity adjacent the actuator; a first
valve member, the movement of the first valve member controlled by
the actuator; a second valve member selectively in contact with the
first valve member; and wherein during a first mode of operation,
the actuator controls the movement of the first valve member
between an open position and a closed position to allow purge vapor
to flow from the cavity through the second valve member and out of
the housing, and in a second mode of operation, when vacuum
pressure in the cavity reaches a predetermined level, the vacuum
pressure in the cavity moves the first valve member and the second
valve member such that air flows into the housing and into the
cavity, relieving the vacuum pressure in the cavity.
2. The apparatus of claim 1, the housing further comprising an
overmold assembly.
3. The apparatus of claim 1, the cavity further comprising an
overmold assembly cavity.
4. The apparatus of claim 1, further comprising: a first port
formed as part of the housing, the first port in fluid
communication with the cavity and a fuel tank; and a second port
selectively in fluid communication with the cavity and a carbon
canister; wherein during the first mode of operation, the actuator
is used to move the first valve member away from the second valve
member, and control the flow of purge vapor flowing from the first
port, through the cavity, and out of the second port, and in the
second mode of operation, vacuum pressure in the cavity moves the
first valve member and the second valve member, allowing air to
pass from carbon canister into the second port and into the
overmold assembly cavity, through the first port, and into the fuel
tank, relieving vacuum pressure in the fuel tank.
5. The apparatus of claim 4, further comprising: a cap connected to
the housing; and a cap aperture formed as part of the cap such that
the cap aperture forms at least part of the second port; wherein
during the first mode of operation, the purge vapor flows from the
first port, the cavity, through the cap aperture, and out of the
second port when the first valve member is in the open position,
and during the second mode of operation, and the vacuum pressure
reaches a predetermined level to move the first valve member and
the second valve member, the air flows from the second port,
through the cap aperture, into the cavity, and out of the first
port.
6. The apparatus of claim 1, the actuator further comprising a
solenoid assembly.
7. The apparatus of claim 1, further comprising an armature
controlled by the actuator, the first valve member connected to the
armature.
8. The apparatus of claim 7, the first valve member further
comprising a stopper portion connected to the armature, wherein the
stopper portion is selectively in contact with the second valve
member as the actuator moves the armature and the stopper portion
between the open position and the closed position.
9. The apparatus of claim 1, the second valve member further
comprising: a core portion selectively in contact with the first
valve member; a flow aperture formed as part of the core portion;
and an outer seal member connected to the core portion; wherein
during the first mode of operation, the first valve member is
selectively moved away from the core portion to control the amount
of purge vapor flow through the flow aperture, and during the
second mode of operation, the vacuum pressure in the cavity moves
the first valve member, the core portion, and the outer seal such
that air is allowed to flow into the cavity of the housing.
10. The apparatus of claim 9, the second valve member further
comprising: a base formed as part of the core portion, the flow
aperture formed as part of the base; a flange member integrally
formed with the base, the flange member being part of the core
portion; and a lip formed as part of the outer seal member; wherein
during the second mode of operation, the lip is selectively in
contact with an inside surface of the cavity such that when the
vacuum pressure in the cavity reaches a predetermined value, the
lip moves away from the inside surface.
11. The apparatus of claim 1, wherein the first valve member and
the second valve member are in the same flow path.
12. A valve assembly, comprising: an overmold assembly; an overmold
assembly cavity formed as part of the overmold assembly such that
the overmold assembly cavity is in fluid communication with a fuel
tank and a carbon canister; an inside surface being part of the
overmold assembly cavity; an actuator disposed in the overmold
assembly adjacent the overmold assembly cavity; a first valve
member connected to the actuator such that the movement of the
first valve member is controlled by the actuator; and a second
valve member selectively in contact with the first valve member and
the inside surface; wherein during a first mode of operation, the
actuator moves the first valve member relative to the second valve
member to control the flow of purge vapor flowing from the fuel
tank, through the overmold assembly cavity, and into the carbon
canister, and in a second mode of operation, the overmold assembly
cavity is exposed to vacuum pressure in the fuel tank such that the
vacuum pressure moves the second valve member and the first valve
member away from the inside surface, allowing air to pass from the
carbon canister into the overmold assembly cavity, and into the
fuel tank, relieving vacuum pressure in the fuel tank.
13. The valve assembly of claim 12, further comprising: an
armature, the armature being part of the actuator; and a stopper
portion connected to the armature, the stopper portion being at
least part of the first valve member; wherein during the first mode
of operation, the stopper portion selectively contacts the second
valve member as the purge vapor flows from the overmold assembly
cavity, out of the overmold assembly and into the carbon
canister.
14. The valve assembly of claim 12, further comprising: a cap
connected to the overmold assembly; and a cap aperture formed as
part of the cap; wherein the purge vapor flows from the overmold
assembly cavity through the cap aperture during the first mode of
operation, and the air flows through the cap aperture into the
overmold assembly cavity during the second mode of operation.
15. The valve assembly of claim 14, further comprising: a first
port formed as part of the overmold assembly, the first port in
fluid communication with the fuel tank; and a second port formed as
part of the cap such that at least a portion of the cap aperture
extends into the second port, the second port in fluid
communication with the carbon canister; wherein during the first
mode of operation and the first valve member is in the open
position, purge vapor flows from the first port into the overmold
assembly cavity, through the cap aperture and through the second
port, and during the second mode of operation and the second valve
member is moved away from the inside surface, air flows from the
carbon canister, through the second port, through the cap aperture
and into the overmold assembly cavity, through the first port, and
into the fuel tank.
16. The valve assembly of claim 12, the second valve member further
comprising: a core portion selectively in contact with the first
valve member; a flow aperture formed as part of the core portion;
an outer seal member connected to the core portion; and a lip
formed as part of the outer seal member; wherein during the first
mode of operation, the first valve member is selectively moved away
from the core portion to control the amount of purge vapor flow
through the flow aperture, and during the second mode of operation,
the vacuum pressure in the overmold assembly cavity moves the first
valve member, the core portion, and the outer seal such that the
lip is moved away from the inside surface, and air flows into the
housing and into the overmold assembly cavity.
17. The valve assembly of claim 16, the second valve member further
comprising: a base formed as part of the core portion, the flow
aperture formed as part of the base; and a flange member integrally
formed with the base, the flange member being part of the core
portion; wherein the outer seal partially surrounds the base and
the flange member.
18. The valve assembly of claim 12, the actuator further comprising
a solenoid assembly.
19. A tank pressure control valve assembly, comprising: an overmold
assembly; a first port formed as part of the overmold assembly, the
first port in fluid communication with a fuel tank; a cap connected
to the overmold assembly; a second port formed as part of the cap,
the second port in fluid communication with a carbon canister; an
overmold assembly cavity formed as part of the overmold assembly,
the first port in fluid communication with the overmold assembly
cavity; an inside surface formed as part of the cap, the inside
surface forming a part of the overmold assembly cavity; a solenoid
assembly disposed inside the overmold assembly adjacent the
overmold assembly cavity; an armature disposed in the overmold
assembly, the movement of the armature controlled by the solenoid
assembly; a stopper portion connected to the armature; a cap
aperture formed as part of the cap, the cap aperture formed as part
of the second port, such that the cap aperture provides fluid
communication between the overmold assembly cavity and the second
port; and a secondary valve member, the stopper portion selectively
in contact with the secondary valve member; wherein during a first
mode of operation, the solenoid assembly is used to move the
armature and stopper portion away from the secondary valve member,
and control the flow of purge vapor flowing from the first port,
through the overmold assembly cavity and the secondary valve
member, and out of the second port, and in a second mode of
operation, vacuum pressure in the overmold assembly cavity moves
the secondary valve member, the stopper portion, and the armature
away from the inside surface, allowing air to pass from the second
port, through the cap aperture and into the overmold assembly
cavity, through the first port, and into the fuel tank, relieving
vacuum pressure in the fuel tank.
20. The tank pressure control valve assembly of claim 19, the
secondary valve member further comprising: a core portion
selectively in contact with the stopper portion and the inside
surface; a flow aperture formed as part of the core portion; a base
formed as part of the core portion, the flow aperture formed as
part of the base; a flange member integrally formed as part of the
base, the flange member being part of the core portion; a outer
seal member substantially surrounding the flange member; and a lip
formed as part of the outer seal member, the lip selectively in
contact with the inside surface; wherein during the first mode of
operation, the stopper portion is selectively moved away from the
core portion to control the flow of purge vapor through the flow
aperture, and during the second mode of operation, the vacuum
pressure in the overmold assembly cavity moves the secondary valve
member, the stopper portion, and the armature such that the lip
moves away from the inside surface.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/861,576 filed Aug. 2, 2013. The disclosure of
the above application is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates generally to a valve assembly which
performs the functions of removing purge vapor from a fuel tank
under pressure, and allowing passive vacuum relief of the fuel tank
as necessary.
BACKGROUND OF THE INVENTION
[0003] The amount of air pressure in a fuel tank varies with
changes in temperature, and changes in the amount of fuel in the
tank, such as during refueling and fuel consumption. In hot
climates, the level of air pressure and amount of purge vapor in
the tank is controlled by opening and closing a valve for very
short pulses. This contains the vapors in the tank as much as
possible, without exceeding a limit pressure for the tank. However,
there are conditions where the tank also needs passive (not
controlled) relief of vacuum pressure. Vacuum pressure in the fuel
tank may occur during periods of fuel consumption during vehicle
operation, and needs to be relieved to avoid reaching an
undesirable level. However, typical valve assemblies are designed
to only provide flow control, and have a separate valve used to
provide vacuum relief.
[0004] Accordingly, there exists a need for a valve assembly which
is able to provide flow control during a purge process, and vacuum
relief.
SUMMARY OF THE INVENTION
[0005] The present invention provides for both controlled flow of
purge vapor and passive vacuum relief functions with an additional
component in a tank purge valve. The invention adds a sealing disk
to a purge valve to create a small sealing area on one side that
opens easily against the tank pressure with the normal magnetic
forces in a purge valve. The sealing disk has an aperture in the
middle to allow for the flow of purge vapor. The second side of the
disk has sealing on a larger area so the small vacuum forces open
the valve against the spring force which biases the valve to a
closed position. The design of the present invention uses a disk to
provide precise flow control and vacuum relief.
[0006] In one embodiment, the invention is a tank pressure control
valve assembly, which includes an overmold assembly having a first
port, where the first port is in fluid communication with a fuel
tank. A cap is connected to the overmold assembly, and a cap
aperture is formed as part of the cap, such that the cap aperture
forms part of a second port, and the cap aperture provides fluid
communication between the overmold assembly cavity and the second
port. The second port is in fluid communication with a carbon
canister. An overmold assembly cavity having an inside surface is
formed as part of the overmold assembly, and the first port is in
fluid communication with the overmold assembly cavity. A solenoid
assembly is disposed inside the overmold assembly adjacent the
overmold assembly cavity, and the solenoid assembly controls the
movement of an armature. A stopper portion is connected to the
armature, and the valve assembly also includes a secondary valve
member, where the stopper portion is selectively in contact with
the secondary valve member.
[0007] During a first mode of operation, the solenoid assembly is
used to move the armature and stopper portion away from the
secondary valve member, and control the flow of purge vapor flowing
from the fuel tank into the first port, through the overmold
assembly cavity, and out of the second port. During a second mode
of operation, the overmold assembly cavity is exposed to vacuum
pressure in the fuel tank, and the vacuum pressure moves the
secondary valve member, the stopper portion, and the armature away
from the inside surface, allowing air to pass from the second port,
through the cap aperture and into the overmold assembly cavity,
through the first port, and into the fuel tank, relieving vacuum
pressure in the fuel tank.
[0008] The secondary valve member has several components. In one
embodiment, the secondary valve member includes a core portion
selectively in contact with the stopper portion and the inside
surface. The core portion includes a base, and a flow aperture is
integrally formed as part of the base. A flange member is also
integrally formed as part of the base, and is part of the core
portion. An outer seal member substantially surrounds the flange
member, and a lip is formed as part of the outer seal member, such
that the lip is selectively in contact with the inside surface.
During the first mode of operation, the stopper portion is
selectively moved away from the core portion to control the amount
of purge vapor flow through the flow aperture. During the second
mode of operation, the vacuum pressure in the overmold assembly
cavity moves the secondary valve member, the stopper portion, and
the armature such that the lip moves away from the inside
surface.
[0009] Further areas of applicability of the present invention will
become apparent from the detailed description provided hereinafter.
It should be understood that the detailed description and specific
examples, while indicating the preferred embodiment of the
invention, are intended for purposes of illustration only and are
not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The present invention will become more fully understood from
the detailed description and the accompanying drawings,
wherein:
[0011] FIG. 1 is a diagram of part of an air flow system for a
vehicle, having a tank pressure control valve assembly, according
to embodiments of the present invention;
[0012] FIG. 2 is a sectional view of a tank pressure control valve
assembly, according to embodiments of the present invention;
and
[0013] FIG. 3 is an enlarged view of the circled portion of FIG.
2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] The following description of the preferred embodiment(s) is
merely exemplary in nature and is in no way intended to limit the
invention, its application, or uses.
[0015] A tank pressure control (TPC) valve having a multi-function
valve assembly is shown in FIGS. 1-3 generally at 10. The TPC valve
10 includes an inlet port 12 in fluid communication with a fuel
tank 86. The TPC valve 10 includes a housing, which in this
embodiment is an overmold assembly 14, and disposed within the
overmold assembly 14 is an actuator in the form of a solenoid
assembly, shown generally at 16, and the solenoid assembly 16 is
disposed within a cavity, shown generally at 18, formed as part of
the overmold assembly 14. The cavity 18 includes an inner wall
portion 20, and also forming part of the cavity 18 is an outer wall
portion 22 of the overmold assembly 14.
[0016] The solenoid assembly 16 includes a stator insert 24 which
surrounds a support 26 formed as part of the overmold assembly 14.
A first washer 28 is disposed between an upper wall 30 of the
overmold assembly 14 and a bobbin 32. The bobbin 32 is surrounded
by a coil 34, and two straps (not shown) surround the coil 34.
There is a sleeve 36 which is surrounded by the bobbin 32, and the
sleeve 36 partially surrounds a moveable armature 38. The armature
38 includes a cavity, shown generally at 40, and located in the
cavity 40 is a spring 42, which is in contact with an inner surface
48 of the cavity 40. The spring 42 is also mounted on a narrow
diameter portion 44 of the support 26, and the spring 42 biases the
armature 38 away from the stator insert 24. Disposed between part
of the armature 38 and the bobbin 32 is a second washer 46.
Connected to the overmold assembly 14 is a cap 50, and formed as
part of the cap 50 is a cap aperture 54 and a second port 68. The
cap aperture 54 is partially formed as part of the second port 68,
and the second port 68 is connected to and in fluid communication
with a carbon canister 88. Purge vapor is able to flow from an
overmold assembly cavity, shown generally at 56, formed as part of
the overmold assembly 14, through the cap aperture 54, and out of
the second port 68.
[0017] The armature 38 includes a first valve member, which in this
embodiment is a stopper portion 58 made of a rubber or other
flexible material. The stopper portion 58 includes a contact
surface 60 which contacts a second or secondary valve member, shown
generally at 70, when the armature 38 is in the closed position.
The stopper portion 58 includes a plurality of post members 62,
which are of the same durometer, but are of different sizes, and
therefore have different levels of stiffness. The largest post
members 62 are in contact with the bottom surface of the washer 46
when the armature 38 is in the closed position, as shown in FIG. 2.
The smaller post members 62 contact the bottom surface of the
washer 46 when the armature 38 moves to the open position. The
spring 42 biases the armature 38 and the stopper portion 58 away
from the stator insert 24 and toward the second valve member 70,
and therefore biases the armature 38 and stopper portion 58 towards
the closed position. The coil 34 is energized to move the armature
38 away from the second valve member 70, placing the solenoid
assembly 16 in an open position. The more the coil 34 is energized,
the further the armature 38 moves away from the second valve member
70, and the greater number of post members 62 contact the bottom
surface of the washer 46. The movement of the armature 38 to open
and close the solenoid assembly 16 controls the amount of purge
vapor allowed to pass through the TPC valve 10, and into the
canister 88.
[0018] Because the post members 62 are made of rubber, the post
members 62 are able to deform as the armature 38 is moved further
away from the second valve member 70. The largest post members 62
in contact with the bottom surface of the washer 46 deform first
when the armature 38 moves away from the second valve member 70. As
the armature 38 moves further away from the second valve member 70,
more of the post members 62 contact the bottom surface of the
washer 46, and then begin to deform as the armature 38 moves even
further away from the second valve member 70. The deformation of
the post members 62 (when the armature 38 is moved to the open
position away from the second valve member 70) functions to dampen
the movement of the armature 38, eliminating noise, and preventing
metal-to-metal contact between the armature 38 and the stator
insert 24.
[0019] Disposed between the bottom surface of the washer 46 and an
inside surface 64 of the cap 50 is a filter 66. The filter 66 is
made of several blades of plastic which are adjacent to one
another. The filter 66 is designed to limit the size of debris and
particles passing through the blades of plastic to less than 0.7
millimeters. The distance between the armature 38 and the stator
insert 24 is about 1.0 millimeters, and is the maximum allowable
distance between the contact surface 60 of the stopper portion 58
and the second valve member 70. The filter 66 ensures that no
particles may pass through the filter 66 that are too large to
affect the functionality of the solenoid assembly 16 (the particles
being too large to fit between the second valve member 70 and the
stopper portion 58) when the armature 38 is in the open
position.
[0020] The second valve member 70 is disposed between the stopper
portion 58 and an area 72 of the inside surface 64 surrounded by
the filter 66. The second valve member 70 includes a flow aperture
74 formed as part of a core portion 76, where the contact surface
60 is in contact with the core portion 76 when the armature 38 is
in the closed position. The core portion 76 includes a base 78 and
a flange member 80, and surrounding part of the base 78 and the
flange member 80 is a outer seal member 82. The seal member 82
includes a lip 84 selectively in contact with the area 72 of the
inside surface 64 surrounded by the filter 66.
[0021] As mentioned above, the more the coil 34 is energized, the
further the armature 38 and the stopper portion 58 move away from
the second valve member 70, placing the solenoid assembly 16 in an
open position, allowing purge vapor to pass from the overmold
assembly cavity 56, through the flow aperture 74, the cap aperture
54 and out of the second port 68. The purge vapor is then able to
flow into the carbon canister 88.
[0022] The valve 10 provides a flow path between the fuel tank 86
and the carbon canister 88, where the flow path includes the inlet
port 12, the overmold assembly cavity 56, the stopper portion 58,
the cap aperture 54, and the second port 68, and during process
when purge vapor is removed from the fuel tank 86, the flow
aperture 74 is part of the flow path as well. The purge vapor flows
through the flow path in one direction, and air for vacuum pressure
relief flows in another direction. Both the stopper portion 58 and
the secondary valve member 70 are disposed in this same flow
path.
[0023] During operation, if there is a need to allow purge vapor to
move from the fuel tank 86 to the carbon canister 88, such as
during times of refueling or an increase in pressure in the fuel
tank 86 due to an increase in temperature, the coil 34 is energized
enough to overcome the biasing force of the spring 42 to move the
armature 38 and the stopper portion 58 away from the second valve
member 70, allowing vapor in the fuel tank 86 to flow in a first
direction and flow from the inlet port 12, through the overmold
assembly cavity 56, through the flow aperture 74 of the second
valve member 70, through the flow aperture 74, and out of the
second port 68, and into the carbon canister 88.
[0024] If the vehicle is operating under conditions such that there
is a vacuum condition in the fuel tank 86, such as during typical
driving when the level of fuel in the tank 86 is reduced as the
fuel is consumed, or because of a decrease in temperature when the
vehicle is parked, air is allowed to pass from the canister 88
through the valve 10 and into the fuel tank 86 to relieve the
vacuum pressure in the fuel tank 86. More specifically, once the
vacuum pressure in the fuel tank 86 reaches a predetermined level,
air is drawn from the canister 88 through the valve 10. The vacuum
pressure applies force to the second valve member 70 such that once
enough force is applied to the second valve member 70 to overcome
the biasing force of the spring 42, the armature 38, the stopper
portion 58, and second valve member 70 move away from the inside
surface 64, such that the lip 84 is no longer in contact with the
inside surface 64, allowing air from the canister 88 to flow from
the canister 88 into the second port 68, the cap aperture 54 and
into the overmold assembly cavity 56; the air then flows through
the first port 12 into the fuel tank 86. The air is drawn past the
second valve member 70, and more specifically the lip 84, because
the lip 84 is moved away from the inside surface 64. The flow of
air from the canister 88 to the fuel tank 86 provides a vacuum
pressure relief function, preventing the vacuum pressure in the
fuel tank 86 from reaching undesirable levels.
[0025] The description of the invention is merely exemplary in
nature and, thus, variations that do not depart from the gist of
the invention are intended to be within the scope of the invention.
Such variations are not to be regarded as a departure from the
spirit and scope of the invention.
* * * * *